.nav-title{
    width: 100%;
    box-sizing: border-box;
    font-size: 40rpx;
    padding-left: 30rpx;
    padding-right: 30rpx;
    position: relative;
  
    top: 0;
    left: 0;
    z-index: 1000;
    background-color: #fff;
    text-align: center;
    .back{
      display: none;
    }
  }
  .white{
      color: #fff;
  }
  .nav-title-back{
    text-align: center;
    .back-wrapper{
      display: inline-block;
      width: 50rpx;
      height: 50rpx;
      position: absolute;
      bottom: 0px;
      top: 0px;
      margin: auto 0;
      left: 15rpx;
    }
    .back{
      display: inline-block;
      width: 20rpx;
      height: 40rpx;
      position: absolute;
      top: 5rpx;
      left: 50rpx;
    }
  
  }
  .bg{
      .back-wrapper{
          border-radius: 50%;
          background-color: rgba(255,255,255,0.9);
          border: 1px solid rgba(218,218,218, 1);
          box-sizing: border-box;
      }
      .back{
          width: 24rpx;
          height: 24rpx;
          left: 12rpx;
          top: 12rpx;
      }
  }
  .title-space{
      width: 100%;
      background-color: #fff;
  }
  .transparent{
    background: none!important;
  }
  .fixed{
    position: fixed;
  
  }